fura-2 am

Fura-2 AM是一种膜渗透的Ca2+(钙离子)指示剂，在细胞内被酯酶esterase转变为Fura-2。Fura-2 AM的荧光发射波长在510 nm左右，在高钙浓度和低钙浓度下分别显示出340和380nm的激发最大值，可以用荧光强度比计算钙离子浓度。

Mag-Fura-2 AM是一种可渗透细胞的荧光镁离子(Mg2+)指示剂，对Mg2+具有高度选择性，相较于其他二价离子(Zn2+、Cu2+和Ca2+)。其对Mg2+的选择性超过13,000倍（Mg2+Kd为1.9 nM，相对于Ca2+Kd的25 μM）。激发和发射峰值（λ）分别为369 nm和511 nm。Mag-Fura-2 AM可作为间接指示ATP消耗/产生的指标。

Fura-FF AM is a cell-permeable acetoxymethyl ester of the fluorescence calcium indicator fura-FF (potassium salt) . As fura-FF AM enters cells, it is hydrolyzed by intracellular esterases to produce fura-FF. Fura-FF is a difluorinated derivative of the calcium indicator fura-2 . Unlike, fura-2, fura-FF has negligible magnesium sensitivity, thus reducing interference from this cation. Fura-FF also has a higher calcium dissociation constant than fura-2 (Kd(calcium) = 6 and 0.14 μM, respectively). However, the spectral properties of fura-FF and fura-2 are similar with fura-FF displaying excitation/emission spectra of 365/514 nm in the absence of calcium, with a shift to 339/507 nm in the presence of a high calcium concentration. Low affinity calcium dyes, including fura-FF, are preferred for studying compartments with high concentrations of calcium, such as mitochondria, or in cell systems that have relatively low calcium buffering capacities, such as neuronal dendrites and spines.

Fura Red AM是一种荧光探针，用于可视化活植物组织中细胞质 [Ca(2+)] 分布，在488 nm激发波长下工作。